Wireless mobile technology has become accepted as a necessary part of the modern work place. Employees use wireless mobile technology to send and receive voice calls, electronic mail (e-mail), instant messages, etc. However, there are a number of environments where this type of universal connectivity is not available and wireless solutions are not acceptable. These include, for example, certain hospital, research, and industrial settings where the powerful emission (e.g., 0.01 to 5 watts) from a mobile device can interfere with the operation of equipment, measurements, or processes. Physically isolated facilities, such as those located underground, are another example where wireless connectivity presents a challenge. Yet another example includes classified environments. In these environments, no radio emitters can be used due to concerns regarding the loss of information. There is a substantial loss of efficiency and an increase in complexity in the chain of command due to the added burden of locating and connecting people.